During the first three or so days after your baby is born, he will pass black, tarry stools (meconium). This is normal. The stools will slowly become lighter in color, less sticky and become more liquid.
If you see blood in your baby's stools, call your health care provider's office for an appointment.
If you breastfeed your baby, the stools will be green-yellow to mustard-yellow, seedy and liquid. If you are only breastfeeding (your baby receives no supplemental feedings), frequent and liquid stools are not a concern or a sign of diarrhea.
If you formula feed your baby, the stools will be darker, more solid and have a stronger smell. Your baby will have fewer stools, and they will be larger than those of a breastfed baby.
It is common for infants to strain while having a bowel movement. This is only a concern if the stool is harder than peanut butter.
Some babies will have a bowel movement every time they eat while others may go several days between bowel movements after breastfeeding is well established. This is only a concern if the stool is hard or if your baby is uncomfortable.